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ancient Egyptian astronomy

Two other astronomical reference systems developed independently in early antiquity, the lunar mansions and the Egyptian
decans. The
decans are 36 star configurations circling the sky somewhat to the south of the ecliptic. They make their appearance in drawings and texts inside coffin lids of the 10th dynasty (about 2100
bce) and are shown on the tomb ceilings of Seti I (1318–04
bce)...

definition

...of which consists of 30°; in this they followed the Babylonians. They further regarded each of these 12 signs as the domicile (or house) of a planet and subdivided each into various parts—
decans of 10° each,
fines (“bounds”) of varying lengths, and
dōdecatēmoria of 2°30′...